A Collaborative Approach for the Development of a Standardized Set of Patient-Centered Outcomes in Head and Neck Cancers.

INTRODUCTION: Head and neck cancers remain a significant health burden worldwide. Standardizing the care provided to these patients through the systematic measurement of established indicators is key to improve their outcomes. The aim of this study was to establish a relevant set of outcome indicators in this condition and identify measurement tools and requirements to do so. MATERIAL AND METHODS: One scientific committee and two regional working groups worked in a stepwise manner to narrow down an initial list of potential outcome indicators retrieved from an exhaustive literature review to a smaller set of outcome indicators according to their clinical practice. This was assessed by one representative of a head and neck cancer patient association until a final set of indicators was reached. RESULTS: A total of 164 outcome indicators comprising case-mix, outcomes, and adverse events dimensions were retrieved from the literature. These were reduced to a working set of 79 outcome indicators by the Scientific Committee and divided into seven categories including demographics, clinical status, tumor-related parameters, nutritional status, treatment, health and quality of life parameters and survival. Subsequently, these indicators were further reduced to a set of 50 indicators by the regional working groups and to a set of 49 indicators by the final Scientific Committee assessment. Finally, the discussed indicators were appraised by a head and neck cancer patient association, which added the 'rehabilitation' category, a key parameter to these patients. CONCLUSION: An initial set of outcome indicators for head and neck cancer was systematically developed aiming to standardize the care provided to these patients across institutions at national level and identify measurement tools and requirements to measure those indicators. This standard set should be continuously improved and consistently adopted in the different clinical and national settings.

Tissue composition and density impact on the clinical parameters for (125)I prostate implants dosimetry.

The MCNPX code was used to calculate the TG-43U1 recommended parameters in water and prostate tissue in order to quantify the dosimetric impact in 30 patients treated with (125)I prostate implants when replacing the TG-43U1 formalism parameters calculated in water by a prostate-like medium in the planning system (PS) and to evaluate the uncertainties associated with Monte Carlo (MC) calculations. The prostate density was obtained from the CT of 100 patients with prostate cancer. The deviations between our results for water and the TG-43U1 consensus dataset values were -2.6% for prostate V100, -13.0% for V150, and -5.8% for D90; -2.0% for rectum V100, and -5.1% for D0.1; -5.0% for urethra D10, and -5.1% for D30. The same differences between our water and prostate results were all under 0.3%. Uncertainties estimations were up to 2.9% for the gL(r) function, 13.4% for the F(r,θ) function and 7.0% for Λ, mainly due to seed geometry uncertainties. Uncertainties in extracting the TG-43U1 parameters in the MC simulations as well as in the literature comparison are of the same order of magnitude as the differences between dose distributions computed for water and prostate-like medium. The selection of the parameters for the PS should be done carefully, as it may considerably affect the dose distributions. The seeds internal geometry uncertainties are a major limiting factor in the MC parameters deduction.